The research project outlined here is closely related to goal # 102 G of the National Institute of Mental Health as listed inthe Omnibus Solicitation for Small Business Innovation Research Grants (PHS 96- 2). The long-term goal of this project is to produce a small, relatively affordable device for testing the force at which cutaneous neuronal afferent receptors are activated, at which research animals produce nociceptive withdrawal reflexes, and at which normal human subjects and patients report touch and pain. This device would provide a useful alternative over present technology in terms of ease and speed of use, accuracy, size, utility, and cost. The specific aims of this proposal are to 1) test and compare different candidate technologies necessary to produce a prototype device in terms of accuracy and reliability, taking into account cost and complexity; 2) test this prototype in primary afferent electrophysiological recording experiments, one situation in which the final, commercial form would be used, and the most objective physiologic measurement; and 3; test the prototype in human mechanical touch and pain measurements, an area in which a large potential market exists. The primary afferent recordings and the human measurements would compare the output of the prototype to measurements provided by the present, low technology approach. The final product of the project could be widely useful for neurologists, neurophysiologists, pharmacologists, psychophysicists, and other practitioners of basic and clinical sciences. PROPOSED COMMERCIAL APPLICATION: The research outlined here will lead to a device for the measurement of force thresholds for electrophysiology, analgesia testing in animals, human psychophysics and clinical neurological testing. The largest market would be if the device becomes a standard tool for pharmacologist and others who do animal analgesia testing, and clinical practitions for patient evaluations. Thus, the potential market size of the device would be approximately - 15,000 in the U.S.A. at a price of approximately $1000 each.